Invariant Fourier-wavelet descriptor for pattern recognition

摘要

We present a novel set of descriptors for recognizing complex patterns such as roadsigns, keys, aircrafts, characters, etc. Given a pattern, we first transform it to polar coordinate (r,θ) using the centre of mass of the pattern as origin. We then apply the Fourier transform along the axis of polar angle θ and the wavelet transform along the axis of radius r. The features thus obtained are invariant to translation, rotation, and scaling. As an example, we apply the method to a database of 85 printed Chinese characters. The result shows that the Fourier-wavelet descriptor is an efficient representation which can provide for reliable recognition.